Terminal connecting blocks, modules or panels are widely used in the telecommunications industry to interconnect equipment and distribution lines, particularly in signal switching or distribution applications. The present invention is concerned with connecting modules or panels which provide for a quick, mechanically secure and electrically sound solderless connection, and easy disconnection, of two or more wires. To this end, prior art connecting modules make unnecessary most pre-connection and post-connection wire conditioning, such as stripping, bending and trimming, and employ insulation displacement or like wire connection methods in which the module terminal exerts a positive grip on an installed wire conductor.
U.S patent application Ser. No. 321,107 by Vachhani, filed Nov. 13, 1981, entitled "Electrical Connector Module", now abandoned, continuation filed Sept. 13, 1984 as Ser. No. 650,252, discloses insulation displacement connecting module which provides for quick, mechanically secure and electrically sound solderless connections The Vachhani device employs a metal split cylinder having an axially extending narrow seam or slot in which a wire may be conected by moving it laterally of its axis into the slot. The edges of the slot slic through the insulation and establish an electrical and mechanical contact with the conductor with a positive gripping force as provided by the resilience of the cylinder cross section. The cylinder is supported in an insulating housing of generally cylindrical shape with a rectangular crosssection, in a coaxial orientation, to form a connector module. The housing is slotted along diagonally opposite corners and the cylinder aligned therein such that one corner slot is aligned with the wire receiving slot in the cylinder. A plurality of modules are individually mounted to extend orthogonally from a planar member to form a multiple connector terminal connecting panel. Installation of a wire in a module is accomplished by laying it to extend through the housing slots, over the cylinder, and using an impact tool to drive the wire down into the split cylinder, which preferably includes a cutting edge opposite the wire receiving slot to trim or sever the excess wire length. An installed wire is thus shielded from others by the housing such that shorting and interference problems are avoided.
Although the Vachhani panel provides for the quick and secure solderless cross connection of a large number of wires at a central location with relatively high density, it does have certain disadvantages. For one, assembly of the panel requires that individual modules be mounted one at a time, such that assembly is time consuming and correspondingly expensive. For another, the diagonal orientation of the wire slots together with the side by side orientation of the housings generally requires that wires be positioned and installed one at a time, such that the installer must continually switch between positioning and inserting operations, which is time inefficient in the consecutive installation of large numbers of wires. In addition, the Vachhani tool needs to be oriented with respect to a housing for proper operation. Finally, the tool includes moving parts and is thus relatively expensive.